Quote Originally Posted by CelestialStick
The real Batman recognizes that he's totally outclassed by a god, and calls in the Justice League, which collectively can beat Cthulu, driving him back into the insane reaches whence he came....
The Justice League actually did fight a Cthulhu-type Thanagerian deity in "The Terror Beyond (2)", though Batman wasn't part of this storyline. It was a combination of Hawkgirl and the decidedly odd triumverate of Aquaman, Dr. Fate, and Solomon Grundy that defeated Icthulhu.